Yeah, I guess you're right. It's in YVR and YYC that I've used PP lounges in the US departure areas a few times. (YYZ and YUL are less common airports for me.) I have accessed the door of a nominally-PP lounge in US departures in YYZ when flying WS, but it was full and not accepting PP at the time. But YYZ isn't terribly relevant for the OP anyway since it has an AC. Anyway, the larger point: PP is, I think, in general more useful in Canada than in the US if you want a lounge-type setting.